Non-consolidated VIEs - Corporation's VI in non-consolidated VIEs and max exposure to loss (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021	Sep. 30, 2021
Variable Interest Entity
Assets	$ 70,729,675	$ 75,097,899	$ 74,189,163
Variable Interest Entity Not Primary Beneficiary
Variable Interest Entity
Assets	107,048	102,432
Maximum exposure to loss	107,048	102,432
Variable Interest Entity Not Primary Beneficiary | Servicing assets
Variable Interest Entity
Assets	100,468	94,464
Variable Interest Entity Not Primary Beneficiary | Mortgage servicing rights
Variable Interest Entity
Assets	100,468	94,464
Variable Interest Entity Not Primary Beneficiary | Other assets
Variable Interest Entity
Assets	6,580	7,968
Variable Interest Entity Not Primary Beneficiary | Servicing advances
Variable Interest Entity
Assets	$ 6,580	$ 7,968